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Abstract The objective of this study is to comprehensively assess the behavior of partially encased concrete (PEC) columns with web openings under axial compression. The primary objectives of this study are to analyze damage patterns and investigate the influence of key parameters, such as concrete strength, opening rate, and opening shape, on the ductility index and ultimate load-carrying capacity. The study employs experimental testing to examine the response of the PEC columns, with a particular focus on the mechanisms of concrete fracture and flange flexing. Notably, the study reveals a significant impact of the opening rate on the bearing capacity, while the effect of opening shape is comparatively minor. Furthermore, computational analyses are conducted to deepen the understanding of structural behavior. The study builds upon existing research to propose a novel method for calculating the bearing capacity of PEC columns with web openings. This method introduces two discount factors to enhance predictive accuracy.

Lithological mapping in highly vegetated areas using remote sensing techniques poses a significant challenge. Inspired by the concept of “geobotany”, we attempted to distinguish lithologies indirectly using machine learning algorithms (MLAs) based on Sentinel-2 and SRTM DEM in Zhangzhou City, Fujian Province. The study area has high vegetation cover, with lithologies that are largely obscured. After preprocessing such as cloud masking, resampling, and median image synthesis, 17 spectral bands and features from Sentinel-2 and 9 terrain features from DEM were extracted. Five widely used MLAs, MD, CART, SVM, RF, and GBDT, were trained and validated for lithological mapping. The results indicate that advanced MLAs, such as GBDT and RF, are highly effective for nonlinear modeling and learning with relative increases reaching 8.18%∼11.82% for GBDT and 6.36%∼10% for RF. Compared with optical imagery or terrain data alone, combining Sentinel-2 and DEM significantly improves the accuracy of lithological mapping, as it provides more comprehensive and precise spectral characteristics and spatial information. GBDT_Sen+DEM utilizing integrated data achieved the highest classification accuracy, with an overall accuracy of 63.18%. This study provides a case study for lithological mapping of areas with high vegetation cover at the local level. This also reinforces the idea that merging remote sensing and terrain data significantly enhances the precision and reliability of the lithological mapping methods.

PD-1 and PD-L1 antibodies have brought about extraordinary clinical benefits for cancer patients, and their indications are expanding incessantly. Currently, most PD-1/PD-L1 agents are administered intravenously, which may be uncomfortable for some cancer patients. Herein, we develop a novel oral-delivered small molecular, YPD-29B, which specifically targets human PD-L1. Our data suggested that YPD-29B could potently and selectively block the interaction between PD-L1 and PD-1, but did not inhibit any other immune checkpoints. Mechanistically, YPD-29B induced human PD-L1 dimerization and internalization, which subsequently activated T lymphocytes and therefore overcomes immunity tolerance in vitro. YDP-29B was modified as the YPD-30 prodrug to improve druggability. Using humanized mice with human PD-1 xenografts of human PD-L1 knock-in mouse MC38 cancer cells, we demonstrated that YPD-30 exhibited significant antitumor activity and was well tolerated in vivo. Taken together, our results indicate that YPD-30 serves as a promising therapeutic candidate for anti-human PD-L1 cancer immunotherapy.

The development of urban underground space and traffic promotes the wide application of large section pipe jacking technology in urban tunnel construction.The functional requirements of parallel pipe jacking tunnel are different, so shapes and sizes of the section are also different.Based on the double-line parallel pipejacking tunnel with difference large section under through the main road in the city, a three-dimensional finite element calculation model is established for systematic analysis.At the same time, combined with the measured results of the field pipe jacking project, the characteristics and influencing factors of ground-surface deformation under different sections and different construction sequence of parallel pipe jacking are studied.The results show that the surface deformation curve caused by parallel differential section pipe jacking construction is Ⅴ-curve, and the peak point of the surface deformation curve gradually shifts from the large section rectangular pipe jacking axis to the two pipe centers.The surface settlement on the left side of the axis of the small section rectangular pipe jacking is larger than that on the right side of the axis.Construction of large section rectangular pipe jacking on the left line is more beneficial to control surface deformation.The influence of section size change on surface deformation is 30%, and the influence of process on surface deformation is 8%.The influence of section size difference on surface deformation is greater than that of process difference.The study on the influence of parallel differential section pipe jacking construction on surface deformation can provide theoretical basis and experience for future related parallel large section pipe jacking projects.

Monitoring of the indicator Sustainable Development Goal (SDG) 11.3.1 is important for understanding the coordination between land consumption rate (LCR) and population growth rate (PGR). However, the spatiotemporal indicator SDG 11.3.1 changes at the urban agglomeration (UA) level, and the relationship between LCR and PGR in the prefecture-level cities from different UAs remains unclear. In this study, we monitored the spatiotemporal indicator SDG 11.3.1 in the Yangtze River Economic Belt (YREB) and its three major UAs (i.e., Chengdu–Chongqing (CC), the Middle Reaches of the Yangtze River (MRYR), and the Yangtze River Delta (YRD)) for the periods 2000–2010, 2010–2015, and 2015–2018, using the space–time interaction (STI) method and Pearson’s method. Our major findings were as follows: (1) Compared with the world average of 1.28 for LCRPGR (i.e., ratio of LCR to PGR), except for the LCRPGR of the YRD (2000–2018) and CC (2000–2010), the LCRPGR of CC, the MRYR, and the YREB was lower than 1.28 during 2000–2018. (2) The gaps in both population and built-up area between the YREB and the three UAs did not narrow, but widened. (3) Compared with the LCRPGR in China, except for the LCRPGR of the YRD (2000–2018) and CC (2000–2010), the LCRPGR of the YREB increased from 1.21 to 1.23 between 2000–2010 and 2010–2015, and then decreased to 1.16 in 2015–2018, indicating that the relationship between LCR and PGR in the YREB is relatively stable. (4) A significant positive relationship (p < 0.001) was found between LCR and PGR in CC, the MRYR, the YRD, and the YREB. We conclude that the indicator SDG 11.3.1 is a helpful tool for evaluating land-use efficiency caused by the LCR and PGR at the UA level. Our results provide information support for promoting sustainable and coordinative development between LCR and PGR.

Understanding the spatial distribution of populations at a finer spatial scale has important value for many applications, such as disaster risk rescue operations, business decision-making, and regional planning. In this study, a random forest (RF)-based population density mapping method was proposed in order to generate high-precision population density data with a 100 m × 100 m grid in mainland China in 2015 (hereafter referred to as ‘Popi’). Besides the commonly used elevation, slope, Normalized Vegetation Index (NDVI), land use/land cover, roads, and National Polar Orbiting Partnership/Visible Infrared Imaging Radiometer Suite (NPP/VIIRS), 16,101,762 records of points of interest (POIs) and 2867 county-level censuses were used in order to develop the model. Furthermore, 28,505 township-level censuses (74% of the total number of townships) were collected in order to evaluate the accuracy of the Popi product. The results showed that the utilization of multi-source data (especially the combination of POIs and NPP/VIIRS data) can effectively improve the accuracy of population mapping at a finer scale. The feature importances of the POIs and NPP/VIIRS are 0.49 and 0.14, respectively, which are higher values than those obtained for other natural factors. Compared with the Worldpop population dataset, the Popi data exhibited a higher accuracy. The number of accurately-estimated townships was 19,300 (67.7%) in the Popi product and 16,237 (56.9%) in the Worldpop product. The Root Mean Squared Error (RMSE) and Mean Absolute Error (MAE) were 14,839 and 7218, respectively, for Popi, and 18,014 and 8572, respectively, for Worldpop. The research method in this paper could provide a reference for the spatialization of other socioeconomic data (such as GDP).

Urban sustainable development has attracted widespread attention worldwide as it is closely linked with human survival. However, the growth of urban areas is frequently disproportionate in relation to population growth in developing countries; this discrepancy cannot be monitored solely using statistics. In this study, we integrated earth observation (EO) and statistical data monitoring the Sustainable Development Goals (SDG) 11.3.1: “The ratio of land consumption rate to the population growth rate (LCRPGR)”. Using the EO data (including China’s Land-Use/Cover Datasets (CLUDs) and the Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) nighttime light data) and census, we extracted the percentage of built-up area, disaggregated the population using the geographically weighted regression (GWR) model, and depicted the spatial heterogeneity and dynamic tendency of urban expansion and population growth by a 1 km × 1 km grid at city and national levels in mainland China from 1990 to 2010. Then, the built-up area and population density datasets were compared with other products and statistics using the relative error and standard deviation in our research area. Major findings are as follows: (1) more than 95% of cities experienced growth in urban built-up areas, especially in the megacities with populations of 5−10 million; (2) the number of grids with a declined proportion of the population ranged from 47% in 1990−2000 to 54% in 2000−2010; (3) China’s LCRPGR value increased from 1.69 in 1990−2000 to 1.78 in 2000−2010, and the land consumption rate was 1.8 times higher than the population growth rate from 1990 to 2010; and (4) the number of cities experiencing uncoordinated development (i.e., where urban expansion is not synchronized with population growth) increased from 93 (27%) in 1990−2000 to 186 (54%) in 2000−2010. Using EO has the potential for monitoring the official SDGs on large and fine scales; the processes provide an example of the localization of SDG 11.3.1 in China.